Optical communication systems include optical amplifiers to amplify optical signals as the optical signals flow through the system. As one example, Raman amplifiers are located in optical nodes that are separated by approximately 80-100 km in the optical communication system. Raman amplifiers provide optical gain (amplification) arising from stimulated Raman scattering. For example, Raman amplifiers include a plurality of Raman pumps that each output an optical signal at different wavelengths, and the combination of the optical signals from the Raman pumps adds to the received optical signal to provide distributed amplification on the optical signal that is received. There may be loss in the optical signal transmitted by a first optical node to the second optical node, and the Raman amplifier in the second optical node amplifies the optical signal that the second optical node receives to compensate for the loss.